四氯化钛除钒尾渣钠化焙烧动力学研究  

Study on sodium roasting kinetics of vanadium removal slag of titanium tetrachloride

作　　者：堵伟桐 姜丛翔 郑睿琦 陈卓 居殿春 Du Weitong;Jiang Congxiang;Zheng Ruiqi;Chen Zhuo;Ju Dianchun(School of Metallurgy and Material Engineering,Jiangsu University of Science and Technology(Zhangjiagang),Zhangjiagang 215600,Jiangsu,China)

机构地区：[1]江苏科技大学张家港校区冶金与材料工程学院,江苏张家港215600

出　　处：《钢铁钒钛》2022年第1期7-12,共6页Iron Steel Vanadium Titanium

基　　金：江苏省自然科学基金青年项目(BK20210888);江苏省高等学校自然科学研究面上项目(20KJB450001,20KJD450001)。

摘　　要：基于非等温热重分析研究Na_(2)CO_(3)添加量和升温速率对含钒尾渣氧化的影响规律,采用Kissinger-AkahiraSunose(KAS)法计算了含钒尾渣氧化过程活化能和指前因子,并通过Coats-Redfem法推断机理函数并建立不同阶段所适用的动力学方程。结果表明:含钒尾渣完全氧化的温度为700℃,随Na_(2)CO_(3)添加量增加,表观活化能逐渐降低,氧化速率提高;当Na_(2)CO_(3)添加量超过20%后,钒渣在氧化焙烧过程中出现玻璃相,产生烧结现象,表观活化能开始逐渐增大,氧化速率降低。钠化焙烧过程分为四个阶段,其动力学方程分别为:第一阶段二维扩散dα/dT=exp(−72.03/RT)4(1−α)^(1/2)[1−(1−α)^(1/2)]20.022/β,第二阶段三维扩散dα/dT=exp(−23.7/RT)^(3/2)(1−α)^(4/3)[(1−α)^(−1/3)−1]^(−1)0.014/β,第三阶段化学反应dα/dT=exp(−27.91/RT)(1−α)^(2)0.06/β,第四阶段形核与长大dα/dT=exp(−12.09/RT)2(1−α)[−ln(1−α)]^(1/2)0.14/β。Based on non-isothermal thermogravimetric analysis,the influences of Na_(2)CO_(3)addition and heating rate on oxidation of vanadium removal slag of titanium tetrachloride(vanadium-containing tailings)were studied.The Kissinger-Akahira-Sunose(KAS)method was used to calculate the activation energy and pre-exponential factor of the oxidation process of vanadium-containing tailings.Through the Coats-Redfem method,the mechanism function was inferred and the kinetics equations of different stages were established.The results show that the temperature for complete oxidation of the vanadiumcontaining tailings is 700℃.With the increase of Na_(2)CO_(3)addition,the apparent activation energy gradually decreases and the oxidation rate increases.While the Na_(2)CO_(3)addition exceeds 20%,the glassy phase appears during the oxidation roasting process which results in sintering,and the apparent activation energy gradually increases with the oxidation rate decreased consequently.The sodium roasting process can be divided into four stages and the kinetics equations are as follows:the first stage of two-dimensional diffusion with dα/dT=exp(−72.03/RT)4(1−α)^(1/2)[1−(1−α)^(1/2)]^(2)0.022/β,the second stage of three-dimensional diffusion with dα/dT=exp(−23.7/RT)^(3/2)(1−α)4/3[(1−α)^(−1/3)−1]−10.014/β,the third stage of chemical reaction with dα/dT=exp(−27.91/RT)(1−α)^(2)0.06/βand the fourth stage of nucleation and growth with dα/dT=exp(−12.09/RT)2(1−α)[−ln(1−α)]^(1/2)0.14/β.

关 键 词：含钒尾渣 钠化焙烧 非等温热重 活化能 动力学方程 

分 类 号：X757[环境科学与工程—环境工程] TF841.3[冶金工程—有色金属冶金]